Concepts in Microbiology Flashcards
What is a ‘Gram Stain’?
A method of staining used to distinguish and classify bacterial species into two large groups - based of their different cell wall constituents
What does Aerobic mean?
In the presence of Oxygen
What does Capnophilic mean?
In the presence of Carbon Dioxide
What does Facultative mean?
In the presence or absence of Oxygen
What does Anaerobic mean?
In the absence of Oxygen
What does Microaerophilic mean?
Requires small amounts of Oxygen
What is Binary Fission?
It is a kind of asexual reproduction - ‘division in half’
What is included in a bacterial cell?
- Outer capsule and protective layers
- Inside the cell
- Pili
- Bacterial components
- Bacterial Flagellum
- The bacteria’s ‘genome’: a circular strand of DNA
What is the name for rod shaped bacteria?
Bacilli
What is the name for round shaped bacteria?
Cocci
What is an endotoxin?
A toxin present inside a bacterial cell that is released when it disintegrates
What is an exotoxin?
A toxin released by a living bacterial cell into its surroundings
What is Leukocidin?
A type of exotoxin produced by pathogenic bacteria; it destroys leukocytes and may also damage monocytes and macrophages
What are gram positive bacteria?
They have a thick peptidoglycan wall
What are gram negative bacteria?
They have a thin peptidoglycan wall
What colour do gram positive bacteria stain?
Violet
What colour do gram negative bacteria stain?
Red
What are prokaryotes characteristics?
- No cell membrane
- No membrane bound organelles
What is an example of a prokaryote?
Bacteria
What are eukaryotes characteristics?
- Cells with nucleus
- Organelles and internal membranes
What is an example of a eukaryote?
Animals
What is non-selective agar?
Agar with animal blood added to provide essential bacteria and will grow a variety of bacteria
What is selective agar?
Agar with additional supplements to supress some types of bacteria but encourage the growth of others e.g. Mannitol agar
What is Chromogenic agar?
Agar that changes colour when bacteria grows on it
